Step-ladder.



P. B. UNDERWOOD.

STEP LADDER.

APPLICATION FILED NOV. 28, 1913.

1,109,559, Patented Sept. 1, 1914.

THE NORRIS FEFERS (70., PHOTO-LHHQ, WASHINGTON. u. L

To all whom it may concern UNITED sTATEs PATENT orFroE.

FRANK B. UNDERWOOD, or NoBLnsvi LE, INDIANA, ASSIGNOR or o E-HALF ro FRED E. HEYLMANN, or NOBLESVILLE, INDIANA.

STEP-LADDER.

PatentedSept. 1, 1914.;

Application filed November 28, 1913. Serial No. 803,597.

, Be it known that I, FRANK B. UNDER- woon, a citizen of the United States, residing at Noblesville; in the county of Hamilton and State of Indiana, have invented certain new and useful Improvements in Step- Ladders, of \vhichthe following is a specification.

This invention relates to improvements in step ladders and has particular reference to the means for attaching and supporting the steps, and the object of the invention is to provide means for drawing the side-bars tightly against the ends of the steps and for attaching the ends of the steps to the sidebars in a firm and solid manner to prevent the tilting of the steps when the supported weight is near the front or back edge of the ladder.

The object also is to provide an inexpensive and durable step-securing means which will'enable any looseness due to wear in the joints between the steps and side-bars to be taken up as it develops thereby enabling the rigidity and safety of the ladder to be constantly maintained.

I accomplish the above and other objects which will hereinafter appear, by the means illustrated in the accompanying drawing, in which- Figure 1 is a perspective view of a step ladder containing my improved mechanism. Fig. 2 is a detail on a larger scale in front edge view of one of the steps shown in Fig. 1, the nut being shown in longitudinal section. Fig. 3 is a section on the line 3"?) of Fig. 2. Fig. 4 is a view of the step holding plate looking at its inner face or face next to the side-bar of the ladder, and Fig. 5 is a front edge view of the plate showing the side-bar in dotted lines.

Like characters of reference indicate like parts throughout the several views of the drawing.

The side-bars 6 are two in number and are preferably formed out of wood, and are con nected by the steps 7, also formed out of wood, and my invention is comprised primarily in the means for securing the steps to the side-bars. Prop-legs 8, having suitable tie-braces 9 and 10, are pivotally secured at their upper ends to the respective side-bars 6 of the ladder, to permit the legs to be folded parallel with the side-bars and in contact therewith when desired.

Located each end of each step 7, be

tween the step-end and the adjacent side-bar 6 of the ladder is a vertical plate 11, having a plurality of lugs or spurs 12 formed integrally on'the side of the plate next to the side-bar 6. These lugs will preferably taper toward their outer ends to facilitate their insertion into holes bored in the side-bar to receive them, said holes being somewhat smaller in diameter than the base-portion of the lug but large enough to receive the small outer end of. the lugs. When the lug thus shaped is driven into the hole in the sidebar as above provided a close fit of the lug will be insured. Formed upon the inner side of the plate 11 are two parallel flanges 13 and 1 1 which are adapted to receive the end of a step between them. These flanges will stand horizontally when the ladder is in a position for use. The plates 11 are also provided with holes below the lower flange 1 1 for the passage through said plates of bolts 15 and 16, as thecase may be. The bolts 15 and 16 have heads 17 on their outer ends, and the inner ends ofthe bolts are screw threaded, right-hand threads being formed upon the bolts 15 and left-hand threads upon the bolts 16. The bolts thus formed are passed through suitable holes in the side-bar 6 and through the registering holes in the plates 11, and their threaded ends are screwed into a cylinder 19 having end bores which are provided with right and left threads to receive the respective bolts 15 and 16. Thecylinder 19 is provided with transverse holes 20 for the insertion of a wrench or lever for rotating the cylinder.

21 are ribs to enter the ends of the steps and hold them from working edgewise.

In assembling the ladder the steps 7 are placed in position between the pair of sidebars 6 with the plates 11 between the bars and the ends of the steps as shown in Fig. 1, and with the bolts 15 and 16 also inserted as shown and entering their respective cylinders v1S). Then by tightening the bolts by rotating the cylinders 19 the side-bars 6 will I be drawn tightly against the plates 11 and 1 as any looseness due to wear develops.

' While I have described my invention with more or less minuteness as regards details of construction and arrangement and as being embodied in. certain precise forms, I do not desire to be limited thereto unduly or an more than is pointed out in the claims. Q11 the contrary I contemplate all proper changes in term, construction, and arrangement, the omission of immaterial elements and the substitution of equivalents as cirbars to prevent turning of the plates on the side-bars. said lugs entering indents in the side-bars, a bolt under each step passing through the plates at the ends of the step. below the flanges for the step said bolts be ing in two parts forming inner ends which are screw threaded and said bolts having heads on their outer ends which contact with the outer sides of the side-bars, and a .inder having screw threaded bores into leh both of the screw threaded ends of bolt members are screwed. in witness whereof, I have hereunto set in hand and seal at Indianapolis, Indiana this 15th day of November, A. D. one thousand nine. hundred and thirteen.

FRANK B. UNDERVVOOD. \Vitnesses F. W. Worsening L. B. Hosanna.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

